from decimal import Decimal
from math import e
def f(n):
numerator = Decimal(1)
for i in range(n,3*n+1):
numerator *= i
return numerator**(1/Decimal(n)) / n / n
print f(10000)
print 27/e/e
ZnJvbSBkZWNpbWFsIGltcG9ydCBEZWNpbWFsCmZyb20gbWF0aCBpbXBvcnQgZQoKZGVmIGYobik6CiAgICBudW1lcmF0b3IgPSBEZWNpbWFsKDEpCiAgICBmb3IgaSBpbiByYW5nZShuLDMqbisxKToKICAgICAgICBudW1lcmF0b3IgKj0gaQogICAgcmV0dXJuIG51bWVyYXRvcioqKDEvRGVjaW1hbChuKSkgLyBuIC8gbgoKcHJpbnQgZigxMDAwMCkKcHJpbnQgMjcvZS9l